Coffee machine



FIG. 1 is a front perspective view of a coffee machine showing my new design;

FIG. 2 is a rear perspective view;

FIG. 3 is a front elevation view thereof;

FIG. 4 is a rear elevation view thereof;

FIG. 5 is a left side elevation view thereof;

FIG. 6 is a right side elevation view thereof;

FIG. 7 is a top view thereof; and,

FIG. 8 a bottom view thereof.

The broken lines in the drawings are included for the purpose of illustration and form no part of the claimed design. 

The ornamental design for a coffee machine, as shown and described. 